1. Field of the Invention
This invention relates to a method and apparatus for separating paper sheets into units and distributing them. The paper sheets to be separated into units and distributed by the apparatus and method of this invention are equipped with markers for grouping them into units, each of which consists of a predetermined number of sheets.
2. Description of the Prior Art
Japanese Laid-Open Patent No. 61-188342 discloses a method and apparatus for separating paper sheets into units and distributing them.
The above-mentioned prior art apparatus comprises: a raising means for raising paper sheets having ream-marker tapes for grouping them into units, each containing a predetermined number of sheets; a separation means for vertically separating paper sheets in accordance with the ream-marker tapes; and a distribution means for distributing the paper sheets thus separated into units by the separation means. The separation means includes an insertion head equipped with suction holes for attracting the ream-marker tapes and an insertion tongue. A plurality of forks are inserted into a paper gap made in a pile of paper sheets by raising a unit of paper sheets from the pile by means of the insertion tongue. The forks are then moved forwards, thus distributing paper sheets by the unit.
However, the above-described apparatus has the following problem: it is not possible to form between the paper sheets a space wide enough to smoothly admit the plurality of forks (arranged at predetermined spaces on both sides of the apparatus) solely by raising paper sheets by means of the insertion head. This is particularly true when the paper sheets are relatively large.
Furthermore, the insertion head of the above-mentioned separation means is designed to attach to the ream-marker tapes by means of vacuum suction holes provided on the lower surface thereof, so that, when the insertion tongue is being inserted into a paper gap over a ream-marker tape, it is likely to hit against the paper sheet which is immediately above the ream-marker tape, thereby damaging this paper sheet. Thus, the separation of paper sheets cannot be performed in a satisfactory manner with this prior art apparatus.
As for the above-mentioned prior art method of separating paper sheets into units and delivering them, it comprises the following steps: first, a pile of paper sheets having ream-marker tapes for grouping them into units is raised to a certain height. The raising movement is stopped when a ream-marker tape is detected, and the insertion head is inserted into the pile at the position indicated by the ream-marker tape. Afterwards, the insertion head is further raised to form a gap in the pile, into which the distributing forks are inserted. Finally, the distributing forks are moved forwards, thus distributing paper sheets by the unit. Thus, this prior art method necessitates a rather long operation cycle.